1. FIELD OF THE INVENTION
The present invention relates in general to the field of beverage dispensing machines, and in particular, in one embodiment, to hot drinks dispensing machines which utilize sachets of beverage-producing material through which a hot liquid passes.
2. DESCRIPTION OF RELATED ART
Prior art beverage dispensing machines which utilize packages of beverage-producing material are well known. In one variation of such known machines, they include a tank of hot water communicating with a water injector in the form of a hollow needle. A sachet of beverage-producing material is inserted into the machine by the user, the injector of the machine pierces a plastic nozzle carried in the top seam of the sachet and hot water is introduced into the sachet. The beverage is dispensed from the machine through the bottom of the sachet. The bottom seam of the sachet is secured by a pressure-sensitive adhesive. This seal is forced open by the pressure of fluid in the sachet. The beverage itself is formed by the hot water mixing with the beverage-producing material as it passes through the sachet. Such a system has been marketed by the assignee of this application, initially under the trade mark "Dimension 3", now "Flavia". Sachets and machines are described, for example, in EP-A-0179641 and GB-A-2122881, and in U.S. Pat. Nos. 4,886,674 and 4,738,378, respectively.
In general, ground coffee or leaf tea is supported upon filter material within the sachets. This arrangement ensures that when the bottom of the sachet opens due to the pressure of hot water in the sachet, the tea leaves or coffee grains are not forced out of the sachet and into the receptacle in which the beverage itself is being collected. Sometimes, however, the opening of the sachet is so explosive and vigorous that a small amount of beverage is sprayed from the bottom of the sachet away from the receptacle below the sachet so that not all of the beverage enters the receptacle. This is clearly undesirable.
Although the aforementioned prior art dispensing machines work satisfactorily when producing coffee or tea, subject to any initial spraying of the beverage as the sachet opens being inexcessive, the machines are less satisfactory for dispensing certain other beverages, such as hot chocolate.
Hot chocolate, for example, is formed by dispersing a powder in a liquid rather than using an infusion technique as in the case of coffee or tea. Accordingly, the hot chocolate powder must be able to pass out of the sachet as the beverage is produced. If a prior art machines is used, this results in the powder as well as the liquid being sprayed out of the bottom of the sachet as the sachet opens explosively. This powder is wasted and causes a mess. Powder can also be ejected into the receptacle insufficiently dispersed in the hot liquid.
In another known variation of machines which produce beverages from packages with pressure-sensitive seals, a sachet with such a seal is compressed externally to rupture the seal and express the sachet contents into a waiting receptacle. Such sachets have typically contained fruit juice or cola concentrates, which are mixed with liquid (typically water-gaseous or non-gaseous as the case may be) dispensed separately into the receptacle. If the sachet opens explosively, as with the first-mentioned version of machines, the expelled product can be ejected vigorously--which is less than satisfactory.